Doepfer

Hi Paul,
Thanks for the info. I have just simulated the 'attack' part of the 
circuitry in the demo versions of PSpice and Multisim that I'm 
currently evaluating. Admittedly neither has the exact models for the 
BC547/549 (they are demo versions after all...), but using two NPN 
transistors whose parameters looked reasonably different, you 
wouldn't have got a fag paper between the two 'envelopes' output! 
This confirms my initial reaction - the differences in the 
transistors probably don't affect the output that much (which is why 
the two types are considered equivalent). I'd still wager any 
difference comes down to the capacitors - I've been wanting to get to 
the bottom of this for other reasons (the quad osc in the frequency 
shifter for one) but have only recently received a book with some 
info that may help, and it's also partly the reason I am evaluating 
the analogue simulation packages, so that I can model different 
effects and see what happens. This is some way off yet, so I'm about 
all out of steam on this for now! If I do have any other ideas I'll 
of course post them.

Tim

--- In Doepfer_a100@y..., Paul Schulz <dasfonk@w...> wrote:
> I noticed some differences in transistors of my ADSRs, too. Okay, 
here 
> we go (components marked on the PCB in brackets)
> 
> A-140 with the flat LED: Q1 to Q4 and Q6: 547 (549);   Q5: 557 (559)
> A-140 with round LED:  Q1and Q2: 549 (549);  Q3, Q4 and Q6: 548 
(549); 
>  Q5: 557 (559)
> 
> Paul  (confused)